Telenomus Dilatus Sp. N. (Hymenoptera: Platygastridae) - an Egg Parasitoid of Swallowtail Butterflies from South India
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ISSN 0973-1555(Print) ISSN 2348-7372(Online) HALTERES, Volume 5, 73- 78, 2014 © RAJMOHANA K. AND MARY ANTO Telenomus dilatus sp. n. (Hymenoptera: Platygastridae) - an egg parasitoid of swallowtail butterflies from South India 1Rajmohana K. and 2Mary Anto 1Zoological Survey of India, Western Ghat Regional Centre, Calicut-673 006, Kerala, India. 2 Research and Post Graduate Department of Zoology, St. Thomas' College, Thrissur- 680 001, Kerala, India. (email: [email protected]) Abstract Telenomus dilatus (Hymenoptera: Platygastridae), an egg parasitoid of swallow tail butterflies is described as new to science. The species has been reared on several occasions in the South Indian State of Kerala, from the eggs of three species of swallow tail butterflies-Troides minos, Pachliopta pandiyana and Pachliopta aristolochiae. T. dilatus sp. n. can be easily distinguished by its basal male antennal segments- A1, A4 and A5, which are extremely dilated. Digital images of the new species are provided and its affinities with closely resembling species are discussed. Keywords:Telenomus, India, swallowtail butterflies, egg parasitoid, new species. Introduction Telenomus Haliday of subfamily South Indian state of Kerala. T. dilatus sp. n. can Telenominae (Hymenoptera : Platygastridae) is a be easily distinguished by its basal male large cosmopolitan genus of egg parasitoids antennal segments, A1, A4 and A5, which are (Johnson, 1984). The hosts are mostly extremely dilated. Earlier Krishnamoorthy and Lepidoptera and Hemiptera, but they are also Singh (1986, 1988) and Veenakumari and known to attack Dipteran and Neuropteran eggs Prasanth 1984, Jalali and Singh, 1990 had (Johnson, 1984; Johnson and Bin, 1982). With reported Telenomus species from the eggs of more than 612 described species, this is the swallowtail butterflies in India. largest genus under Platygastridae (Austin et al. 2002). Altogether 22 species of Telenomus are Materials and methods known from India (Rajmohana, 2006, This work is a part of the ongoing Rajmohana et al. 2013a, 2013b). Though studies on the systematics of Telenominae in economically significant as biocontrol agents, South India. Morphological terminology is after the systematics of this genus is largely ignored Johnson (1984), Miko et al. 2007 and male (Johnson, 1984). genitalia studies follow Polaszek and Kimani The present study describes a new species of (1990). The holotype comparisons of T. stigis Telenomus reared from the eggs of three species Nixon are from the excerpts of the studies of papilionid butterflies, which include, the (Unpublished) on Nixon’s type specimens of Indian peninsular endemic, Troides minos (the Indian Telenominae made by the first author, in Southern Birdwing), the south Indian endemic 2007, during a study visit to BMNH, London. Pachiolopta pandiyana (the Malabar Rose) and Description and light microscopy also Pachiolopta aristolochiae (the Common imaging were done with the help of Leica Rose), which enjoys a wide distribution in South M205A stereomicroscope and Leica DFC-500 and South east Asia. The new species described digital camera and images processed using LAS here has been reared on several occasions in the montage. The SEM images were procured with 73 (Online: 9-January-2015; Print: 9- January-2015) Rajmohana K. and Mary Anto Jeol JCM-5000 NeoScope Benchtop SEM, using between antenna insertions and inner orbit; inner specimens coated with gold. orbits rounded at level of lateral ocelli; LOL: All the material studied are deposited in POL= 4.5:10; malar sulcus unusually wide National Zoological Collection, of Zoological towards orbital corner; temples not bulging Survey of India, Calicut. laterally; antenna 11 segmented, claval segments Abbreviations and Terminology: A1- 5; A2 2x as long as wide, subequal to A3, A3 A11: Antennal segments 1 to 11; T1-T2: length >A4 length (1.2x), A7-A10 transverse. Metasomal tergites 1 to 2; L= Length; W= Mesosoma: (L:W =101:95); Width; DCI-Dorsal Cephalic Index (ratio of mesoscutum not as wide as head dorsally width to length of head measured dorsally; (23:26); distinctly convex when viewed LOL=Lateral ocellar length; POL= Posterior laterally, notauli absent; densely setose; ocellar length sculptured uniformly with rough scaly BMNH-Natural History Museum, London; reticulations; scuto-scutellar sulcus narrow NZC- National Zoological Collection; ZSIC- medially, but laterally wide and foveolate; Zoological Survey of India, Calicut, Kerala. humeral sulcus elongate, not foveolate; mesoscutellum smooth throughout; pubescence Systematics not as dense as on mesoscutum; lower margin Telenomus dilatus Rajmohana et Anto, sp. n. evenly curved, submarginal foveae smaller than (Figs. 1-9) dorsellar punctures; dorsellum longest medially and overlapping propodeum; coarsely reticulate urn:lsid:zoobank.org:act:A1B7807C-C79F- anteriorly, but distally with irregular 424D-8505-F52E748994A9 longitudinal rugosities; acetabular field almost bare; episternal fovea absent; intercoxal space Material examined: Holotype ♀: India: slightly exceeding length of forecoxa; netrion Kerala: Trichur, on 27.vi.2000 (Reg.No. smooth; mesopleural furrow distinct, but ZSI/INV/4126, reared from eggs of Troides mesopleural carina absent; metapleuron bare and minos. Paratypes 2 ♂ (4127-4128) and 10 ♀ smooth medially, except for fine traces of a few with data same as holotype (4129-4139); 1 ♂ crenulae; metapleural carina indicated as a short and 1 ♀ (4140 and 4141) emerged on spur posteriorly; forewing at rest surpassing 4.vii.2000 from Pachliopta pandiyana eggs and apex of metasoma; hindwing at its widest point 2 ♀ (4142-4143) on 1.xii.2010, from eggs of as long as length of marginal fringe; forewing Pachliopta aristolochiae. All specimens reared L:W= 26:9; post marginal vein much longer by Mary Anto from Trichur. than stigmal vein. Metasoma: (L:W= 10.2:5.6), slightly Description less than 2x as long as wide; very slightly longer Holotype. Female. Body length than combined length of head and mesosoma; =1.01mm. Head and body light to dark brown T1 with longitudinal striae extending nearly to to black; antennae as well as coxae brownish its three-fourth; 2 pairs of sublateral setae yellow, fore coxae and claval segments darker; distinct; greatest length of basal costae on T2 eyes silvery; wings hyaline. along with fine longitudinal wrinkles, 2x Head: distinctly transverse ; DCI=2.3; median length of T1, extending nearly to dorsal vertex and occiput with fine coriaceous one-fourth. reticulate sculpture and with scattered and Male: Length 1.03mm. Resembles superimposed setigerous punctures; more female, except in aspects mentioned below. coriaceous towards vertex; vertex deeply cut to Antenna with 12 segments, A1 unusually occiput; hyperoccipital carina seen as a trace; dilated, wide medially; A4 and A5, subequal, eyes large, densely pilose; occipital carina extremely dilated or enlarged, A4 slightly and simple and complete; orbital band wide, not A5 distinctly curved medially, A6 to A11 more interrupted medially; frons width > eye or less globular, A9-A10 transverse; A12 height(9:8.5); two pairs of ocellar setae distinct; elongate, 1.1x longer than A10 and A11 frontal depression weak, frons not bulging 74 Telenomus dilatus sp. n. - an egg parasitoid of swallowtail butterflies from South India 1 2 3 4 5 Figs.1-7: Telenomus dilatus sp. n. (Female) 1.Body Profile; 2. Mesosoma profile; 3. Antenna; 4. Head frontal view; 5. Mesoscutum dorsal view. 75 Rajmohana K. and Mary Anto 6 7 Figs.6-7: Telenomus dilatus sp. n. (Female) 6. Mesoscutellum and dorsellum; 7. Metasoma. 8 9 Figs.8-7: Telenomus dilatus sp. n. (Male) 8. Antennae; 9. Genitalia. 76 Telenomus dilatus sp. n. - an egg parasitoid of swallowtail butterflies from South India combined. Male metasoma (L:W= 85:57), dilatus sp. n. (A5 is nearly 1.5x as long as A4 in widest towards lower T2. T. stigis, and A4 is only very slightly longer than Male genitalia: Resembling much that of A3 in T. stigis). Female antenna is 11 segmented T. talus Nixon and T. stigis Nixon as per the in T. dilatus (in both T. talaus and T. stigis medially drawn, tapered and truncate towards female antenna are 10 segmented only). tip, one third the length of aedeago volsellar shaft; laminae volsellares sclerotized; digiti Acknowledgements large, nearly 0.5x maximum length of aedeagal The first author is thankful to the lobe, with 3 teeth per digitus; central projection Director, Zoological Survey of India, and absent. Officer-in-Charge, ZSI, Calicut for Host: Eggs of swallowtail butterflies- encouragement and facilities provided. She is Troides minos, Pachliopta pandiyana and also thankful to The Museum of Comparative Pachliopta aristolochiae. Zoology, Harvard, for the award of Ernst Mayr Etymology: The species is named Travel Grant, for a visit to BMNH, London, to ‘dilatus’ after the dilated appearance of the basal study the Types specimens of Telenominae of male antennal segments. Indian Region and also to Platygastroidea Planetary Biodiversity Inventory project, for Discussion literature support. The second author would like T. dilatus sp. n. belong to Telenomus to acknowledge the help rendered by her guide, californicus species complex, as per Johnson, Dr. George Mathew and the institutional support 1984. Though the females of T. dilatus do not from the Kerala Forest Research Institute, possess any prominent or peculiar distinguishing Peechi, Kerala. features, the male antenna with its enlarged A1, A4 and A5 serve as a strong diagnostic character References